This study will explore whether viral replication can be successfully suppressed in nucleoside analog-experienced patients with advanced HIV infection using the substitution of potent new agents including indinavir sulfate (IDV, a protease inhibitor); DMP-266 (a non-nucleoside reverse transcriptase inhibitor [NNRTI]) currently being studied in combination with IDV; and 1592U89 (a nucleoside analog reverse transcriptase inhibitor). A total of 450 subjects will be enrolled over a 3-month period. Eligible subjects will discontinue treatment with ZDV (or d4T) and 3TC and be randomized with equal likelihood (stratified by CD4+ count and participation in ACTG 320) to either: 1) IDV 1000mg TID (q8hours)+DMP-266 600mg qd+1592U89 placebo BID 2) IDV 1000mg TID (q8hours)+DMP-266 600mg qd+1592U89 300mg BID 3) IDV 800mg TID (q8hours)+DMP-266 placebo qd+1592U89 300mg BID. Subjects will be followed for the safety and tolerability of the drug combinations and the effect of the regimens on plasma HIV-RNA, CD4+ and CD8+ cells, quality of life, and clinical progression for 48 weeks beyond the enrollment of the last subject. Subjects with a confirmed detectable plasma HIV-RNA (2 consecutive levels>200 copies/mL) at week 16 or thereafter will have the option to receive open-label IDV, DMP-266 and 1592U89.